Brown azo dye.



WILI-IELM IBERGDOL'I, OF LEVERKUSEN, NEAR COLOGNE, GERMAN PAENT OFFICE.

siIGNOit TO FARBENFAIBRIKEN VORIVI. FRIEDR. BAYER 8c (10., OF ELBERFELD, GER-MANY, A

CORPORATION OF GERMANY.

BROWN A20 DYE.

neonate.

No Drawing.-

Specification of Letters Patent.

Application filed July 6, 1911.

Patented Nov. 28, 1911. Serial No. 637,157.

(R an aryl c. g. C l-L, -C H -NU -C H CH,, C H OOH X=H or SO H; X H or CH Y=H or OH) can be obtained by combining the tetrazo com pounds of a para-diamin of the benzidin series such as benzidin, tolidin, nitrobenzidin, dianisidin, with one molecule of a diamin c. g. toluylenedia-min, meta -phenylenediamin, meta-phenylenediamin sulfonic acid and one molecule of a phenol such as phenol or resorcin. i

The new dyes are brown powders yielding upon treatment with stannous chlorid and hydrochloric acid a diamino diaryl com pound, a triamin of the benzene series and an aminophenol. Very valuable yellowish brown shades fast to washing are obtained by treating with diazot-ized nitranilins cotton dyed with these new dyes. The shades thus obtained are especially valuable for the reason that they can be remarkably well discharged to a pure white.

In order to illustrate the new process more fully I give the following example, the parts being by weight-22.9 parts of nitrobenzidin are tetrazotized with 14 parts of sodium nitrite and hydrochloric acid. The

' excess of free acid is neutralized with carbonate of sodium and to the diazo solution at 0 a solution of 21.5 parts of the sodium salt of meta-phony]enediamin sulfonic acid is added. After the addition of soda the mixture stirred until the intermediate compound is produced and then a solution of 9.8 parts of phenol in 40 parts of a sodium carbonate solution is added thereto. The mixture is stirred during about 10 hon the dye is salted out, filtered off, and dried. It is a brown powder having most prolnibly the formula:

soluble in water with a. yellow color, yielding upon reduction with stannous chlorid and hydrochloric acid triaminodiphenyl, l.3.6triaminobenzenel-sulfonic acid and para-aminophenol.

I claim The herein described new tetrazodyes obtainab le from paradiamins, diamins, and phenol substanceswhieh are brown powders yielding upon reduction with stannous chlorid and hydrochloric acid a diaminodiaryl compound, a triamin and an aminophenol, furnishing yellowislrbrown shades fast to washing which can be well discharged by treating cotton dyed with these dyes with diazotized nitranilins, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

Monies of this patent may be obtained for five cents each, by addressing the "Commissioner VVILHELM BERGDOLT. [1 s.] Witnesses:

Cnms. J. WRIGHT, ALBERT F. NUFER.

of Patents,

We shine-ton. D. U.

(inflection in Letters Patent No. '1,G9,952.

It is hereby certified that in Letizei's Patent No. 1,009,952, granted November 1911, upon the application of Wilhelm Bergdolt, of Leverkuseu, near Cologne, Ge1'- many, for an improvement in Brown A20 Dye, an error appears in the printed specification requiring correction as follows: Lines 566S2, formula, for

' SOaH NHQ' NO: NO;

c5Hl-x=N o5xii-on end that the said Letters Patent should be reazi with this correction therein that the same may conform to the record of the case in the Patent Ofic-e.

Signed and sealed this 6th day of February, A. 1)., 1912.

O. C. BILLINGS,

A cling Gama missions? of Pa'uents.

[SEAL-1 

